scholarly journals Electrical Neuroimaging with Irrotational Sources

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Rolando Grave de Peralta Menendez ◽  
Sara Gonzalez Andino
Keyword(s):  
Source Localization ◽  
Source Model ◽  
Dispersive Media ◽  
Helmholtz Decomposition ◽  
Static Approximation ◽  
Electrical Neuroimaging ◽  
Density Vector ◽  
First Time ◽  
The Brain ◽  
Primary Current

This paper discusses theoretical aspects of the modeling of the sources of the EEG (i.e., the bioelectromagnetic inverse problem or source localization problem). Using the Helmholtz decomposition (HD) of the current density vector (CDV) of the primary current into an irrotational (I) and a solenoidal (S) part we show that only the irrotational part can contribute to the EEG measurements. In particular we present for the first time the HD of a dipole and of a pure irrotational source. We show that, for both kinds of sources,Iextends all over the space independently of whether the source is spatially concentrated (as the dipole) or not. However, the divergence remains confined to a region coinciding with the expected location of the sources, confirming that it is the divergence rather than the CDV that really defines the spatial extension of the generators, from where it follows that an irrotational source model (ELECTRA) is always physiologically meaningful as long as the divergence remains confined to the brain. Finally we show that the irrotational source model remains valid for the most general electrodynamics model of the EEG in inhomogeneous anisotropic dispersive media and thus far beyond the (quasi) static approximation.

scholarly journals Spatiotemporal Processing of Bimodal Odor Lateralization in the Brain Using Electroencephalography Microstates and Source Localization

2021 ◽  
Vol 14 ◽  
Author(s):  
Christine Ida Hucke ◽  
Rebekka Margret Heinen ◽  
Marlene Pacharra ◽  
Edmund Wascher ◽  
Christoph van Thriel
Keyword(s):  
Source Localization ◽  
Superior Temporal Gyrus ◽  
Odor Perception ◽  
Visual Spatial ◽  
Spatiotemporal Processing ◽  
Continuous Eeg ◽  
First Time ◽  
The Brain ◽  
Airborne Chemicals ◽  
Healthy Participants

The neuronal cascade related to the perception of either purely olfactory or trigeminal airborne chemicals has been investigated using electroencephalography (EEG) microstate analyses and source localization. However, most airborne chemicals are bimodal in nature, encompassing both properties. Moreover, there is an ongoing debate regarding whether there is one dominant nostril, and this could be investigated using these multichannel EEG methods. In this study, 18 right-handed, healthy participants (13 females) were monorhinally stimulated using an olfactometer with the bimodal component acetic acid during continuous EEG recording. Participants indicated the side of stimulation, the confidence in their decision, and rated the strength of the evoked perception. EEG microstate clustering determined four distinct maps and successive backfitting procedures, and source estimations revealed a network that evolved from visual-spatial processing areas to brain areas related to basic olfactory and trigeminal sensations (e.g., thalamus, cingulate cortex, insula, parahippocampal, and pre-/post-central gyri) and resulted in activation of areas involved in multisensory integration (e.g., frontal-temporal areas). Right-nostril stimulation was associated with faster microstate transition and longer involvement of the superior temporal gyrus, which was previously linked to chemical localization and provides evidence for a potential nostril dominance. The results describe for the first time the processing cascade of bimodal odor perception using microstate analyses and demonstrate its feasibility to further investigate potential nostril dominance.

Information-based decoding of the coupling among human brain activity and movement paths

2021 ◽  
pp. 1-10
Author(s):  
Shahul Mujib Kamal ◽  
Norazryana Mat Dawi ◽  
Hamidreza Namazi
Keyword(s):  
Brain Activity ◽  
Point Of View ◽  
Physiological Signals ◽  
Human Walking ◽  
Eeg Signals ◽  
Rehabilitation Science ◽  
Information Contents ◽  
First Time ◽  
The Brain ◽  
Brain Reaction

BACKGROUND: Walking like many other actions of a human is controlled by the brain through the nervous system. In fact, if a problem occurs in our brain, we cannot walk correctly. Therefore, the analysis of the coupling of brain activity and walking is very important especially in rehabilitation science. The complexity of movement paths is one of the factors that affect human walking. For instance, if we walk on a path that is more complex, our brain activity increases to adjust our movements. OBJECTIVE: This study for the first time analyzed the coupling of walking paths and brain reaction from the information point of view. METHODS: We analyzed the Shannon entropy for electroencephalography (EEG) signals versus the walking paths in order to relate their information contents. RESULTS: According to the results, walking on a path that contains more information causes more information in EEG signals. A strong correlation (p= 0.9999) was observed between the information contents of EEG signals and walking paths. Our method of analysis can also be used to investigate the relation among other physiological signals of a human and walking paths, which has great benefits in rehabilitation science.

scholarly journals Biosynthesis of anandamide and N-palmitoylethanolamine by sequential actions of phospholipase A2 and lysophospholipase D

2004 ◽  
Vol 380 (3) ◽  
pp. 749-756 ◽  
Author(s):  
Yong-Xin SUN ◽  
Kazuhito TSUBOI ◽  
Yasuo OKAMOTO ◽  
Takeharu TONAI ◽  
Makoto MURAKAMI ◽  
...  
Keyword(s):  
Biosynthetic Pathway ◽  
Brain Homogenate ◽  
Wide Distribution ◽  
Rat Tissues ◽  
Lysophospholipase D ◽  
Pla2 Enzyme ◽  
First Time ◽  
Hydrolysis Of ◽  
The Brain

Anandamide (an endocannabinoid) and other bioactive long-chain NAEs (N-acylethanolamines) are formed by direct release from N-acyl-PE (N-acyl-phosphatidylethanolamine) by a PLD (phospholipase D). However, the possible presence of a two-step pathway from N-acyl-PE has also been suggested previously, which comprises (1) the hydrolysis of N-acyl-PE to N-acyl-lysoPE by PLA1/PLA2 enzyme(s) and (2) the release of NAEs from N-acyllysoPE by lysoPLD (lysophospholipase D) enzyme(s). In the present study we report for the first time the characterization of enzymes responsible for this pathway. The PLA1/PLA2 activity for N-palmitoyl-PE was found in various rat tissues, with the highest activity in the stomach. This stomach enzyme was identified as group IB sPLA2 (secretory PLA2), and its product was determined as N-acyl-1-acyl-lysoPE. Recombinant group IB, IIA and V of sPLA2s were also active with N-palmitoyl-PE, whereas group X sPLA2 and cytosolic PLA2α were inactive. In addition, we found wide distribution of lysoPLD activity generating N-palmitoylethanolamine from N-palmitoyl-lysoPE in rat tissues, with higher activities in the brain and testis. Based on several lines of enzymological evidence, the lysoPLD enzyme could be distinct from the known N-acyl-PE-hydrolysing PLD. sPLA2-IB dose dependently enhanced the production of N-palmitoylethanolamine from N-palmitoyl-PE in the brain homogenate showing the lysoPLD activity. N-Arachidonoyl-PE and N-arachidonoyl-lysoPE as anandamide precursors were also good substrates of sPLA2-IB and the lysoPLD respectively. These results suggest that the sequential actions of PLA2 and lysoPLD may constitute another biosynthetic pathway for NAEs, including anandamide.

NO nerves in a tapeworm. NADPH-diaphorase histochemistry in adult Hymenolepis diminuta

Parasitology ◽  
1996 ◽  
Vol 113 (6) ◽  
pp. 559-565 ◽  
Author(s):  
M. K. S. Gustafsson ◽  
A. M. Lindholm ◽  
N. B. Terenina ◽  
M. Reuter
Keyword(s):  
Nitric Oxide ◽  
Nervous System ◽  
Nadph Diaphorase ◽  
Hymenolepis Diminuta ◽  
Staining Reaction ◽  
Internal Seminal Vesicle ◽  
Oxide Synthase ◽  
First Time ◽  
The Brain ◽  
Nerve Cords

SUMMARYThe free radical nitric oxide (NO), which is synthesized by nitric oxide synthase (NOS), has recently been discovered to function as a neuronal messenger. The presence of NOS was detected in the nervous system of adult Hymenolepis diminuta with NADPH-diaphorase (NADPH-d) histochemistry. The NADPH-d histochemical reaction is regarded as a selective marker for NOS in neuronal tissue. NADPH-d staining was observed in nerve fibres in the main and minor nerve cords and the transverse ring commissures, and in cell bodies in the brain commissure, along the main nerve cords, in the suckers and the rostellar sac. NADPH-d staining was also observed in the wall of the internal seminal vesicle and the genital atrium. The pattern of NADPH-d staining was compared with that of the 5-HT immunoreactive nervous elements. The NADPH-d staining reaction and the 5-HT immunoreactivity occur in separate sets of neurons. This is the first time the NADPH-d reaction has been demonstrated in the nervous system of a flatworm, indicating that NOS is present and that NO can be produced at this level of evolution.

Cocaine Dependence Produce Psychiatric Symptoms - a Case Report

2009 ◽  
Vol 24 (S1) ◽  
pp. 1-1
Author(s):  
M. Stankovic ◽  
S. Vucetic-Arsic ◽  
S. Alcaz ◽  
J. Cvejic
Keyword(s):  
Clinical Features ◽  
Male Patient ◽  
Psychiatric Symptoms ◽  
Cocaine Dependence ◽  
Psychotic Symptoms ◽  
Personal Contact ◽  
Outpatient Unit ◽  
Special Hospital ◽  
First Time ◽  
The Brain

Aim:We want to present a polymorphic clinical features like: hallutinations, paranoid ideas, agitation and violence as a result of prolonged cocaine intranasal consumption.Methods:We exposed a 30-year old male patient with ICD-X diagnostic criteria for cocaine dependence (intranasal consumption) that treated in the outpatient unit of Special Hospital of Addicitons, Belgrade, Serbia from April to July 2008. We used the medical records, psychical examination, psychiatric interwievs, standard blood sampling and cocaine urine detections sample (positive).Results:Observations a specific and polymorphic clinical features with presence of psychotic symptoms after cocaine consumptions in our male patient, for the first time after 5 years of cocaine dependence: auditory hallucinations (two- voice speakers), paranoid persecution ideas and suspiciousness, agitation with appearance of vegetative symptomatology (palpitations, sweating, pupil dilatation), extremely violence behavior to other people, complete social reductions (“armed to the outside world”, refused any personal contact and isolated from friends and family, permanent outdoor checking). There was an intensive fear too and impaired judgment.Conclusions:Permanent cocaine consumption can result with produce a numerous of psychiatric symptoms and syndromes as our experience does. It is similar to the findings of other studies and papers reviewed. It is suppose that cocaine has numerous effects on important neurotransmitters in the brain, such as increase as well as the release of dopamine and it related with aggressiveness, hallucinations and other psychiatric symptoms.

Information-based analysis of the coupling between brain and heart reactions to olfactory stimulation

2021 ◽  
pp. 1-11
Author(s):  
Najmeh Pakniyat ◽  
Mohammad Hossein Babini ◽  
Vladimir V. Kulish ◽  
Hamidreza Namazi
Keyword(s):  
Time Series ◽  
Biomedical Science ◽  
Strongly Correlated ◽  
Eeg Signals ◽  
Ecg Signals ◽  
Olfactory Stimuli ◽  
Electrocardiogram Ecg ◽  
First Time ◽  
Electroencephalogram Eeg ◽  
The Brain

BACKGROUND: Analysis of the heart activity is one of the important areas of research in biomedical science and engineering. For this purpose, scientists analyze the activity of the heart in various conditions. Since the brain controls the heart’s activity, a relationship should exist among their activities. OBJECTIVE: In this research, for the first time the coupling between heart and brain activities was analyzed by information-based analysis. METHODS: Considering Shannon entropy as the indicator of the information of a system, we recorded electroencephalogram (EEG) and electrocardiogram (ECG) signals of 13 participants (7 M, 6 F, 18–22 years old) in different external stimulations (using pineapple, banana, vanilla, and lemon flavors as olfactory stimuli) and evaluated how the information of EEG signals and R-R time series (as heart rate variability (HRV)) are linked. RESULTS: The results indicate that the changes in the information of the R-R time series and EEG signals are strongly correlated (ρ=-0.9566). CONCLUSION: We conclude that heart and brain activities are related.

scholarly journals Elephant Herding Optimization for Energy-Based Localization

2018 ◽  
Author(s):  
Sérgio Correia ◽  
Marko Beko ◽  
Luís Cruz ◽  
Slavisa Tomic
Keyword(s):  
Source Localization ◽  
Wireless Sensors ◽  
Performance Comparison ◽  
Sensor Nodes ◽  
Convex Relaxations ◽  
Noisy Environments ◽  
New Approach ◽  
Metaheuristic Methods ◽  
Simulation Results ◽  
First Time

This work addresses the energy-based source localization problem in wireless sensors networks. Instead of circumventing the maximum likelihood (ML) problem by applying convex relaxations and approximations (like all existing approaches do), we here tackle it directly by the use of metaheuristics. To the best of our knowledge, this is the first time that metaheuristics is applied to this type of problems. More specifically an elephant herding optimization (EHO) algorithm is applied. Through extensive simulations, the key parameters of the EHO algorithm are optimized such that they match the energy decay model between two sensor nodes. A detailed analysis of the computational complexity is presented, as well as performance comparison between the proposed algorithm and existing non-metaheuristic ones. Simulation results show that the new approach significantly outperforms the existing solutions in noisy environments, encouraging further improvement and testing of metaheuristic methods.

scholarly journals Galectin-3 in the Gut-liver axis Regulates Autistic-like Behaviors by Mechanism Associated with Cerebral Shank-3+ cell Niches in BALB/c Mice

2021 ◽  
Author(s):  
Felipe Lemos ◽  
Caio Prins ◽  
Raul Carpi-Santos ◽  
Ingrid Waclawiak ◽  
Sofia Santos ◽  
...  
Keyword(s):  
Histological Analysis ◽  
Oral Intake ◽  
Cell Junctions ◽  
Cow’S Milk ◽  
Ki 67 ◽  
Autistic Behavior ◽  
Cow's Milk ◽  
Galectin 3 ◽  
First Time ◽  
The Brain

Abstract Galectin-3 stabilizes cell-cell junctions and regulates inflammatory pathways in the gut-liver axis. Galectin-3 knockout (Lgals3−/−) mice have atypical behaviors by obscure mechanisms. Given that BALB/c mice naturally develop low-sociability, stereotypies and restrict interest, they have been included as autism experimental model. Our major aims were to investigate whether galectin-3 in the gut-liver axis interferes with autistic-like behaviors analyzing BALB/c Lgals3−/− mice or under partial inhibition of galectin-3 oral intake of cow’s milk for 7 days. Behavioral patterns were assessed using a three-chambers test, open field, and self-grooming. Histological analysis and immunohistochemistry (Galectin-3, NOS-2, Iba-1, Ki-67, Dll-4, Shank-3, Synaptophysin and Drebrin) were performed in gut, liver, and/or brain. Lgals3−/− mice amplified stereotypies, social retraction and restrict interest associated with reduction of cerebral Shank-3+ cells. In Lgals3+/+ mice, cow’s milk intake also amplified atypical behaviors, reduced galectin-3 in enterocytes and Kupffer cells, and disturbed niches of intestinal KI67+ and Dll-4+ cells and hepatic NOS2+ cells. In the brain of milk-treated mice, Iba-1+ microglial cells and NOS2+ Purkinje cells were increased whereas Shank-3+ and Drebrin+Synaptophysin+ cells were reduced suggesting, for the first time, that galectin-3 interferes with autistic behavior. Perhaps, a perspective to new therapies in genetically predisposed individuals to atypical behaviors.

Source Localization of Subtopographic Brain Maps for Event Related Potentials (ERP)

2008 ◽  
pp. 1247-1252
Author(s):  
Adil Deniz Duru ◽  
Ali Bayram ◽  
Tamer Demiralp ◽  
Ahmet Ademoglu
Keyword(s):  
Source Localization ◽  
Temporal Frequency ◽  
Event Related Potentials ◽  
Functional Brain Imaging ◽  
Frequency Content ◽  
Brain Potentials ◽  
Functional Brain ◽  
Brain Responses ◽  
Related Potentials ◽  
The Brain

Event-related potentials (ERP) are transient brain responses to cognitive stimuli, and they consist of several stationary events whose temporal frequency content can be characterized in terms of oscillations or rhythms. Precise localization of electrical events in the brain, based on the ERP data recorded from the scalp, has been one of the main challenges of functional brain imaging. Several currentDensity estimation techniques for identifying the electrical sources generating the brain potentials are developed for the so-called neuroelectromagnetic inverse problem in the last three decades (Baillet, Mosher, & Leahy, 2001; Koles, 1998; Michela, Murraya, Lantza, Gonzaleza, Spinellib, & Grave de Peraltaa, 2004; Scherg & von Cramon, 1986).

Lewy Body Disease

2021 ◽  
pp. 18-41
Author(s):  
Vaibhav Walia ◽  
Munish Garg
Keyword(s):  
Diagnostic Criteria ◽  
Lewy Body ◽  
Lewy Body Disease ◽  
Composition Formation ◽  
Intracytoplasmic Inclusions ◽  
First Time ◽  
The Brain

Fritz Heinrich Lewy described the intracytoplasmic inclusions found in the neurons for the very first time. In 1919 these inclusions were termed as “LBs” by Tretiakoff. LBs were found in the brain of the patients suffering from Lewy body disease (LBD). LBD is characterized by the presence of Parkinsonian symptoms in the earlier stages and dementia in the later stages of the disease. LBs were classified on the basis of the region of the brain in which they are distributed and so is the case of the LBD means the type of the LBD depends on the anatomical areas of the brain involved. LBD is not a single disorder. It is a spectrum of disorders. This chapter addresses the entire profile of LBs, types, composition, formation, and various LB pathologies as well as diagnostic criteria and pharmacotherapy.

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